The present invention relates to a self-ignition or compression ignition internal combustion engine having combustion chambers for high ignition pressures.
With vehicle engines that are customary these days, especially engines for commercial vehicles, ignition pressures are customary that place very high requirements on the sealing of the combustion chambers and expose the components that are adjacent to the combustion chamber, especially the cylinder head, to very high thermal and mechanical stresses. As a consequence of these high stresses, the cooling effect that can be made available to the combustion chamber cover via the cooling channels in the cylinder head is often not sufficient for an adequate cooling, especially in the regions between the valves. As a result, so-called web or element cracks can occur between the valve openings in the cylinder head and destroy the cylinder head and hence the engine.
In parallel to this existing problem, in order to achieve the emission values required in the future on the one hand, and the constantly increasing requirements for the per liter efficiency of the internal combustion engines while at the same time reducing the weight on the other hand, it would be absolutely necessary to increase the ignition pressures to a magnitude of up to 300 bar, which is nearly double the present standard. Such requirement, at acceptable expense of the material that can be used, cannot be fulfilled with today's customary engine constructions.
It is therefore an object of the present invention to provide an internal combustion engine that is able to cope with high ignition pressures at acceptable structural expense.